Lab 1

Question 1

What two refinements do the system of specialized organs in large animals require?

Answer 1

1. A transport (circulatory) system to carry the gases to and from the cells.
2. A blood pigment which can increase the gas capacity of the transporting fluid. In many animals the pigment used for this task is haemoglobin (Hb).

Question 2

Due to conformation changes in the Hb molecule, what happens when it binds to its first O2 molecule.

Answer 2

It has a greater affinity for O2, which facilitates the binding of the other three O2 molecules.

Question 3

What does the actual amount of oxygen that binds to the hemoglobin depend on?

Answer 3

On the partial pressure of oxygen (PO2) in the tissues or at the gas exchange organ(s)